Understanding "Arc Force" and how to set for different rods

[aland]

I have done some searching and I find advice to either turn up or turn down the Arc Force, but can't find a good explanation of what Arc Force actually does.

From the manual:

"Controls the arc response when an arc is held short and voltage begins to drop. Arc
force automatically compensates by modifying the volt/amp curve to maintain the
energy needed to weld. Represented as a percent of available amperage."

I don't fully understand how the percentage effects how the arc functions, does anyone understand that who could explain it?

How does this pertain to different rod, say for 6011, 6013, 7018, 7024 ?

Alan

[Rambozo]

As you shorten your arc length, the voltage drops. Since the amps stays the same on a constant current machine, the overall power drops. (Power = Volts * Amps) Then the puddle cools a little and before you know it you have stuck the rod and the arc goes out. By having the arc force turned up, as the voltage drops the amperage goes up so you keep the same power and the rod doesn't stick. Most of the time this is a good thing. However, for thin materials like sheet metal, it can also cause you to blow holes in your work, so for that you turn it down. Different rods and applications require different settings. It is a neat feature that lets you keep a really tight arc without sticking the rod. It's one of those features that makes you look better than you are, as it will compensate for slight variations in arc length. It does require a slight change in technique, since with it on, you close the arc length to get more power instead of opening it up. That mainly applies to 6010/6011 where the old technique was to whip and pause. Inverters don't like a long arc, and will shut down if the voltage goes too high, so you have to keep a short arc and use the arc force to get the dig you want. That's why on some machines the arc force control is labeled "Dig".

[aland]

As you shorten your arc length, the voltage drops. Since the amps stays the same on a constant current machine, the overall power drops. (Power = Volts * Amps) Then the puddle cools a little and before you know it you have stuck the rod and the arc goes out. By having the arc force turned up, as the voltage drops the amperage goes up so you keep the same power and the rod doesn't stick. Most of the time this is a good thing. However, for thin materials like sheet metal, it can also cause you to blow holes in your work, so for that you turn it down. Different rods and applications require different settings. It is a neat feature that lets you keep a really tight arc without sticking the rod. It's one of those features that makes you look better than you are, as it will compensate for slight variations in arc length. It does require a slight change in technique, since with it on, you close the arc length to get more power instead of opening it up. That mainly applies to 6010/6011 where the old technique was to whip and pause. Inverters don't like a long arc, and will shut down if the voltage goes too high, so you have to keep a short arc and use the arc force to get the dig you want. That's why on some machines the arc force control is labeled "Dig".

This was part of my problem when I was padding beads several days ago. I had my arc force set to 45% and I was having some intermittent problems with the electrode sticking some.

This makes sense the way you describe it, and also why I was probably not getting very good results with 6011 also, as I didn't change the arc force at all when going between different electrodes. Thanks for the explanation.

I also found a couple pages that Jody Collier put up over on WeldingTipsAndTricks talking about arc force.

http://www.weldingtipsandtricks.com/arc-force.html

http://www.weldingtipsandtricks.com/...g-project.html

Alan

[aland]

Rambozo,

I've been anxious to try this out with more arc force, but unfortunately have been under the weather with the flu...

Got me to thinking though, does this mean if you had it on 100% the amps wouldn't change as the arc gets shorter or longer?

Is it a bad idea to have it on 100%? I'll try turning it up some, but not all the way and experiment with it, was just curious if
you know the answer to that? I probably won't be able to get to this for a couple days with the way I have been feeling...

Alan

[Rambozo]

If you have it on 0% it will be effectively turned off. At 100% you will get the maximum amount that it can deliver. Some machines have separate voltage and current settings, but most group those together in one control, and some have an auto control with no settings. Once you use it, you will find it is pretty easy to understand what the effects are. A lot depends on how consistent a welder you are. In theory if you hold the arc length exactly the same, all the time, you would only find that your amps setting is slightly off what you set it for. On the other hand if you are all over the place with arc length it cannot compensate for that. However, in between those extremes is where it can help you get a more consistent weld, and not have the rod stick if you get a little too close.

[aland]

If you have it on 0% it will be effectively turned off. At 100% you will get the maximum amount that it can deliver. Some machines have separate voltage and current settings, but most group those together in one control, and some have an auto control with no settings. Once you use it, you will find it is pretty easy to understand what the effects are. A lot depends on how consistent a welder you are. In theory if you hold the arc length exactly the same, all the time, you would only find that your amps setting is slightly off what you set it for. On the other hand if you are all over the place with arc length it cannot compensate for that. However, in between those extremes is where it can help you get a more consistent weld, and not have the rod stick if you get a little too close.

I am anxious to try this out, and just trying to recover here from the flu...feeling a bit better today, so maybe tomorrow or Sat.

What you have explained is very helpful, and I understand now that the amperage actually does change depending on the arc, that is something I hadn't known. Is using the length of arc a technique that would allow you to heat and cool the puddle in the case where arc force is not available on a welder? IOW, is that something a welder would do? If I think about whip and pause, it seems to do just that, but with 7018 is more drag. However, I understand what you were originally saying, that if the puddle cools too much, that is when the electrode will stick to the weld, and that was a small issue that I was having and believe I was keep the arc longer to prevent that.

I will certainly pay closer attention when I can get to the welder soon, but just curious if changing the arc is something that a welder could use in a difficult situation where arc force is not available on the welder itself?

Thanks for you help in explaining this, much appreciated.

Alan

[Rambozo]

Typically with 6010 you use arc length to change the puddle characteristics, as you weld. So much technique depends on the machine. Every type of machine has a different volt/amp curve, and responds differently to varying arc lengths. An SA200 has to be one of the best machines for running 6010, as you have control over the curve by using different ranges, fine current control and arc length. It is extremely forgiving, and very controllable with technique. Some new inverters have even tried to emulate an SA200 in software.
Arc force can give you some of that kind of control, but the technique is slightly different.

Rods like 7018 you tend to just hold as tight an arc as you can, and try not to vary that.

[aland]

Typically with 6010 you use arc length to change the puddle characteristics, as you weld. So much technique depends on the machine. Every type of machine has a different volt/amp curve, and responds differently to varying arc lengths.

And to make it more complicated many machines, including mine, have the point gap to toss into the equation, but that seems to only effect tig.

An SA200 has to be one of the best machines for running 6010, as you have control over the curve by using different ranges, fine current control and arc length. It is extremely forgiving, and very controllable with technique.

Although I intended on needing stick when I bought my machine, I upgraded from the PowerArc 200 which was arguably a much better stick machine to the i-Tig 201 because in the long run I think tig will be more useful for the type of work I do, and is just cleaner in general.

Alan

[Rambozo]

The points are only used for the HF start. You can still lift start TIG without them being used. And there are some machines that can use HF start even with stick. But that's really cheating. Using HF start and a foot pedal with stick welding does allow you to do some interesting stuff. I've done it on rare occasions.

[aland]

The points are only used for the HF start. You can still lift start TIG without them being used. And there are some machines that can use HF start even with stick. But that's really cheating. Using HF start and a foot pedal with stick welding does allow you to do some interesting stuff. I've done it on rare occasions.

Is that true for most machines that support a pedal ? Or is that a special feature on specific machines ? I seem to recall the pedal is not active on stick for my machine, but I'll need to check on that.

Alan

[Rambozo]

Is that true for most machines that support a pedal ? Or is that a special feature on specific machines ? I seem to recall the pedal is not active on stick for my machine, but I'll need to check on that.

The pedal is usually not active in stick mode. There is an aftermarket unit called an Arc Pig, that adds HF to any stick welder. A standard TIG power supply is a CC machine and can usually be used for stick welding with any and all TIG features like HF and pedal. However, Everlast has mentioned that they do not support stick welding in TIG mode. Probably something unique to inverters, because it is no problem on transformer or engine drive machines.

[aland]

The pedal is usually not active in stick mode. There is an aftermarket unit called an Arc Pig, that adds HF to any stick welder. A standard TIG power supply is a CC machine and can usually be used for stick welding with any and all TIG features like HF and pedal. However, Everlast has mentioned that they do not support stick welding in TIG mode. Probably something unique to inverters, because it is no problem on transformer or engine drive machines.

Yes, I thought this is what I remember reading, that it was not supported. I just wasn't sure if that was the case for low end vs. the high end units.

As a side note, I was just reading on a machining forum about a machinist I've known for a while passed away after a bad case of the flu...that scares the crap out of me, I don't think he was much older than me...pretty glad I've been cautious this week...it is cold this year on the west coast. I'm no youngster, but still want to spend time with my kids for a number of years to come...be careful out there guys! It's easy to go into the shop when it's cold and start working when you're sick, take your jacket off as you start getting warm, and you just get sicker and sicker...being exposed to the cold...

Alan

[Rambozo]

Yes, I thought this is what I remember reading, that it was not supported. I just wasn't sure if that was the case for low end vs. the high end units.

More a case of old vs. new.
Most older machines are just constant current power supplies. How you use them is a matter of what features you turn on and off. They didn't have a "stick mode" or a "TIG mode". For stick welding you just turn off the remote functions and HF start and such. Just like you can TIG weld with a machine that was designed mainly for stick. You just don't have any special TIG features. So you use a torch with a hand valve, and scratch start. Many many TIG roots have been laid down on pipe using a very plain SA200.
My first TIG rig was an AC/DC buzz box and a shop made TIG torch adapter.

[aland]

Ram,

When you mention SA200 you're talking about those old pipeline welders, right?

I've seen where people convert arc welders to lift start tig, but wasn't exactly clear on the details. In the case of my machine it handles the scratch/lift, but it seems that lift start is something added, maybe I'm wrong. On a normal Lincoln tombstone buzz box, if you converted it would you need to use scratch start rather than lift start ? Or would lift start work also ?

Nowadays it's so cheap to buy a nice inverter stick welder, and it's lunch box size for the most part, plus most all of them have DC tig capability on them.

Alan

[Rambozo]

While the 200 is no more, Lincoln still sells several 300 models of DC generator welders, even today. They are unique machines and weld like nothing else.

Lift start requires circuitry in the machine to limit current for starting, scratch start is full current starting, so it requires that the touch be very brief so the tungsten doesn't stick. There are a few techniques to make this happen. You can tap the tungsten, strike it like a match, or use the filler rod to bridge a gap between the tungsten and the workpiece. That last one is often used for welds that will be X-ray checked to make sure there is no tungsten contamination of the weld. Jody at Welding Tips and Tricks has a video showing a few different ways to scratch start. If using a machine without a lift start function, you have to use scratch start. You can even use a couple of car batteries as a welding power source for stick or TIG. Off road guys use that for field repairs, to limp home.

[aland]

Rambozo,

Whew, been pretty wacked out with the flu for the past couple weeks, but feeling way better and venturing in the shop today...feels good for a change, I've been cooped up in the family room with my laptop...

Wow does that make a difference on the 7018, I played around with moving the arc force up and it made a huge difference in maintaining the arc without sticking.

I didn't try any 6011 yet, mostly out of excitement with the 7018, but it started to get pretty hot as I was padding beads, so will drag a steel pan in to fill with water to dip it. I know that's not recommended but for practice I've seen Jody Collier recommending to use some water to cool it as there's so much heat being applied when you pad beads with stick.

More news at 11:00, as they say. New auto-darkening helmet makes a HUGE difference also...I got a Miller.

Alan

[aland]

Rambozo,

Getting more comfortable with 7018, just burned through about 6-8 electrodes...I burned a couple 6011 and a 6013 also just for $#!T$ and giggles...it will run 6011, not great, but at least it will run it if needed.

I've got my arc force set to about 60% with 120 amps using 1/8" Excalibur.

Was using 70 amps on both 6011 and 6013 with same arc force. Those are 3/32" electrodes. On the pack it said 50-70 amps.

Getting a bit more consistent at restart.

I would like to practice more tig, but I need to take care of a couple stick projects and want to keep focused on it.

Thanks for the help, it's taken a while for me to test some of this out but getting there and making progress.

Alan

[aland]

First experience with arc blowout this evening. I had been welding with 1/8" 7018 Excalibur, 120 amps, 60 % arc force on 1/4" thick plate.

Switched over to 1/8" angle iron, half the thickness and left the amps the same....well, I learned quickly that you don't need to hang on the puddle as long with 1/8", it blew a section about 1"-2" long, along the crease of the angle. I saw some sparks and slag blow out on the floor but didn't think too much about it...now I know to watch closer.

For filling a hole in with 7018 should I turn the amps down some so that it will cool faster over the void?

Alan

[performance]

Yes, of course. You need to turn it down. I'd say you probably should try around 80 to 90 to fill.

[aland]

Yes, of course. You need to turn it down. I'd say you probably should try around 80 to 90 to fill.

Mark,

One thing I was trying to figure out was if 7018 was ok to fill with, or if some other rod is better? I'll try with less amps to fill that...I wish it would warm up...but I'm probably in one of the mildest climates of folks on this fora...LOL

I think I'll wear my leather apron after last night....LOL I have some leather hybrid sleeves, but more protection can't be a bad thing...

Alan